audiophool

After limping through the last winter with the original battery and charging it every few days (date code 4807 stamped on one terminal), I got a proper Interstate replacement and fitted it yesterday.

I didn't bother trying any 'keep alive' duting the swap but could have using the 'supply' mode on my C-Tek charger. I just thought there would be more risks than just doing a dead change.

First start and I got the usual litany of errors including 4x4, DSC and such, plus the main cooling fan went into hurricane mode. Shut off and re-started and it was OK. Set the clock and date and went for a little drive.

Went out a bit later and the clock had reset to 00:00. WTF? Over the last year or so, the clock and trip ODO would reset randomly but now I'm wondering whether it has anything to do with the battery.

The starter cranks much faster now, and the battery voltage holds a lot higher during crank (used to hit about 9V, now 12V). I'd previously assumed the high voltage drop was resetting the time/ODO.

Thoughts? I may need to book it into the stealer to have the charging system initialized - not looking forward to being raped by them (saved about $200 by changing the battery myself).

I've had the fan go on hurricane mode once or twice in the past and re-starting solved it then as now.

What a strange car.

CertifiedOfficial

These things are very sensitive to dying batteries...

Have you registered the new battery so the car knows it's a new battery? That should be your next step, and may help with the errors. Probably not a bad idea to have the new battery and alternator checked for free at an auto parts store, too.

jtbgonesailing

Might want to look at the BMWhat app for diagnostic code reading/coding and the ability to register a new battery. Probably be cheaper for app setup than trip to dealer or maybe Indy to have battery registered.

audiophool

Alternator is working just fine. With a DMM on the jump leads I get a steady 14.4V immediately after starting.

I'll check into the app too.

andymax

New Batteries need a few good charge/discharge cycles on them. At best they've been sitting for a while with an occasional maintenance charge. More likely, they've been sitting on a shelf for months which leads to sulfation. Lead-Acid batteries do not sit well, and will lose up to 3% per day on self discharge depending on environment. When you install it in your car and start it, it draws it down even further. It would probably take a couple hour drive to get it charged back up to close to full.

Best thing you can do is put it on a charger overnight, or a day if using a battery tender.

KyleB

did you change battery type?

audiophool

Andymax: Interstate Battery has a local distribution center here and supplies the parts store with fresh batteries on demand rather than have them sit at the parts stores (or so I'm told). Prior to installation, I had the C-Tek run a proper charge overnight anyway.

KyleB: no, both types FLA (gurgle gurgle)

And it seems to have settled down today, no drama. I'm keeping my eyes on it. Thanks for the input - appreciated.

CertifiedOfficial

Hopefully it was a temporary condition...

kbm9763

I replaced the battery in my 2010 535i last month. Went to Pep Boys and picked up a Bosch battery for $150 after coupon and had it registered by my local independent BMW shop for $30.

twh

kbm9763, what shop did you use to register the battery?